$ git clone -n https://github.com/xcp-ng-rpms/sm.git /var/lib/mock/v8.3-u-prebuild-9343-28100/root/chroot_tmpdir/scmroot/sm
Cloning into '/var/lib/mock/v8.3-u-prebuild-9343-28100/root/chroot_tmpdir/scmroot/sm'...
$ git fetch origin 608a79d6d66769687bda31b67a1d99bac204efa4:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/sm
 * [new ref]         608a79d6d66769687bda31b67a1d99bac204efa4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 608a79d bump release for test build